function navshow(oLi){
    for(var i=0;i<oLi.length;i++){
        oLi[i].oTimer = null;
        oLi[i].alpha = 60;

        oLi[i].onmouseover = function(ev){
            startFilter(this,100);
            this.style.background = "#ffffff";
        }

        oLi[i].onmouseout = function(){
            startFilter(this,60);
        }

        oLi[i].onmousedown = function(){
            this.style.background = "#eeeeee";
        }

        oLi[i].onmouseup = function(){
            this.style.background = "#ffffff";
        }
    }
}
function startFilter(obj,Target){
    clearInterval(obj.Timer);
    if(Target==100)
        obj.className = "shadow";
    obj.Timer = setInterval(function(){
        var speed = (Target-obj.alpha)/10;
        speed = speed>0?Math.ceil(speed):Math.floor(speed);
        if(obj.alpha==Target){
            clearInterval(obj.Timer);
            if(Target==60){
                obj.style.background = "";
                obj.className = "";
            }
        }else{
            obj.alpha += speed;
            obj.style.filter = 'alpha(opacity:'+ obj.alpha +')';
            obj.style.opacity = obj.alpha/100;
        }
    },20);
}
